Why does the high temperature centrifugal fan show strong vibration

- Apr 17, 2019-

When the high-temperature centrifugal fan is used for a long time, certain vibrations will occur due to certain faults. There are many reasons for the vibration. Next, we will introduce you in detail:

1. The influence of process piping

The inlets of high-temperature centrifugal fans are less than 5m apart. They are installed in parallel. The distance from the two exit ducts to the hurricane is about 1.5m. There is no smooth transition. In this way, the airflow is not smoothly discharged, especially the air inlet of the high-temperature centrifugal fan, and the recoil effect of the outlet airflow from the air outlet of the high-temperature centrifugal fan is also encountered. It can not be discharged in time and smoothly. The inlet of the high-temperature centrifugal fan has a feeling of pressure. The pressure of the casing intensifies the vibration of the casing, so that the vibration of the inlet of the high-temperature centrifugal fan is significantly higher than that of the high-temperature centrifugal fan.

2. Influence of high temperature centrifugal fan impeller, shaft and bearing

The impeller of the high temperature centrifugal fan is statically unbalanced. The vibration of the fan shaft is very small, which eliminates the possibility that the fan shaft and the motor shaft do not cause vibration of the fan body; the temperature and vibration of the high temperature centrifugal fan are lower than the specified standard, and there is any miscellaneous in the bearing housing. This in turn indicates that the bearing quality is poor or the installation: the possibility of vibration caused by the qualification does not exist. Even if the fan shaft and the bearing vibrate, the vibration of the fan casing caused by this will not be obvious. The high-temperature centrifugal fan has no contact point with the shaft, the impeller and the fan casing, and the vibration law of the fan casing does not occur. The sex changes with the opening of the entrance door.

3. The influence of the rigidity of the high temperature centrifugal fan shell

The fan shell has been fixed on the concrete foundation with forty bolts to meet the installation requirements; the inlet and outlet flange coupling bolts of the high-temperature centrifugal fan are all filled with spring pads, and there is no other phenomenon; the fan inlet and outlet air ducts are also fixed firmly. There is no obvious instability. It should be said that the rigidity of the fan casing and the air duct is sufficient. The assumption is not enough, which will result in its natural frequency ̧ the frequency of the impeller rotation is close to causing resonance, causing strong vibration.

4. The effect of high temperature centrifugal fan regulating door

The high-temperature centrifugal fan adjustment door is composed of l2 guide vanes. Through the different connection modes of the link mechanism and the guide vanes, the guide vanes can be rotated in both clockwise and counterclockwise directions, so that the inlet of the high-temperature centrifugal fan is clockwise. Or counterclockwise pre-winding, when the wind direction of the fan inlet is the same as the direction of rotation of the impeller, the airflow smoothly and smoothly enters the impeller, and the vibration of the fan casing is small.